The field of the invention generally pertains to restraint and safety harnesses, and more particularly to a slip-retarding upper torso restraint harness and system for supporting a pilot of an aircraft or land vehicle during sudden dynamic load conditions typically associated with a crash impact.
Various types of safety harness and restraint systems have been developed and used in aircraft and land-based vehicles to protect pilots and drivers alike in a crash. In particular, four, five, or six-point anchor systems featuring a pair of shoulder webbings have been commonly used in such heavy-duty applications as military aircraft and racing cars. Typically, the shoulder webbings extend down over the shoulders of an occupant from one or two anchor points behind the head of the occupant, and connect directly or indirectly with a lap webbing anchored to side anchors.
One example of a vehicle safety belt system is shown in U.S. Pat. No. 4,175,787 having a single, continuous length of seat belt webbing forming a pair of shoulder belt portions secured at an upper area of a seat backrest. The shoulder belt portions are passed down and through side anchors located at the bottom of a seat on opposite sides of an occupant, and redirected as lap belt portions around the lap of the occupant. The lap and shoulder belt portions are interconnected above the side anchors by guide members sewn to the lap belt portions.
Similar to patent ""787, a combined shoulder harness and lap belt restraint apparatus is disclosed in U.S. Pat. No. 4,231,616. The apparatus has first and second lap belt portions secured to side anchors located at the bottom of a seat on opposite sides of an occupant. Additionally, first and second shoulder straps extending over the occupants shoulders from a head anchor point are passed down and through the side anchors and affixed to the respective lap belt portions at intermediate points thereon. In this manner, the lap belt and shoulder straps can be simultaneously tightened or released by a single fasten/release point, which greatly conveniences and facilitates the strap-down securing process.
In U.S. Pat. No. 5,524,928 an automobile restraint system is disclosed having a pair of shoulder webs extending over the shoulders of a passenger from behind the seat to connect with a central web anchored at the forward edge of the seat. A pair of retaining webs intersect the respective left the right shoulder webs and extend outwardly to side anchors located on opposite sides of the passenger. During deceleration, the system engages the upper inside portions of the thighs and the shoulders of the passenger, thereby preventing contact of the webs with the neck, chest, or central torso portions of the passenger.
And finally, in U.S. Pat. No. 4,854,608 a torso restraint is shown utilizing a central buckle to releasably secure two lap belts with two shoulder straps which extend over the shoulders of an occupant from a rear anchor point. The two shoulder straps resiliently elongate asymmetrically during an impact and permit the rotation of the torso and a subsequent forward displacement of one shoulder relative to the other shoulder. However, while functioning to absorb and dissipate kinetic energy, any movement of the upper torso during a crash can pose a risk to the pilot by increasing the chances of coming into contact with an interior surface of a vehicle.
While the devices disclosed in patents ""787, ""616, ""928, and ""608 each achieve their respective objectives of restraining an occupant of a vehicle during a crash impact, they do not adequately address the unique problems associated with aircraft crashes, particularly helicopter crashes. One particular problem often seen in helicopter crashes is slippage of the upper torso beneath, and relative to, the shoulder webbings. Upper torso slippage can occur in helicopter crashes due to a combination forward inertial displacement and lumbar compression of the upper torso.
Lumbar compression is the axial compression of the spine which can cause sudden slack in the shoulder webbings. Lumbar compression can result because of the steep descent and impact angles of helicopters while remaining generally level. When the spine compresses, the upper torso can continue to move forward for a momentary duration after the shoulder webbings have locked into place. Consequently, a second impact can take place between the pilot and the restraint harness which can greatly magnify the severity of the injury as compared to injury from the initial crash impact alone. This can occur even when the restraint harness is snugly secured on the pilot during regular operation.
Moreover, upper torso slippage and movement can be especially fatal in helicopter crashes because of the close proximity of the flight control stick to the upper torso of the pilot. While both airplane and helicopter are controlled and operated by means of flight control sticks, helicopter control sticks typically extend up from between the pilot""s legs a greater distance than do most airplane control sticks, and can pose a greater risk in the event of a crash. Thus, there is a need to further reduce upper torso slippage and movement during a crash, particularly a helicopter crash, in order to prevent possible greater injury to the upper torso, and thereby improve crash survivability.
It is an object of the present invention to provide a slip-retarding upper torso restraint harness having a pair of shoulder webbings which minimize the slippage experienced by the upper torso of a pilot of a vehicle along inner surfaces of the shoulder webbings during a crash impact.
It is a further object of the present invention to provide a slip-retarding upper torso restraint system utilizing the slip-retarding upper torso restraint described above, together with a friction-inducing one-piece pilot suit to further prevent slippage along the inner surfaces of the shoulder webbings during a crash impact.
The present invention is for a slip-retarding upper torso restraint harness and system for use with a seat in a vehicle, for supporting a pilot of the vehicle during sudden dynamic load conditions associated with a crash impact. The restraint harness is capable of being positioned over the respective left and right shoulders of the pilot, and comprises elongated left and right shoulder webbings each having first and second ends, and inner and outer surfaces. Each of the second ends are retractably secured by retractor means to a stationary structure on the vehicle near an upper portion of the seat. And each of the inner surfaces have a friction area affixed to the respective inner surface. The restraint harness also includes at least one elongated base webbing having a coupling end and an anchor end secured to a lower portion of the seat, and means for releasably securing together the first ends of the elongated left and right shoulder webbings and the coupling end of the elongated base webbing. In this manner, the friction areas of the elongated left and right shoulder webbings function to minimize upper torso slippage along the inner surfaces of the elongated left and right shoulder webbings when sudden dynamic load conditions are experienced during a crash impact. Additionally, the slip-retarding upper torso restraint system further includes a one-piece pilot suit, preferably having secondary friction areas, utilized in combination with the slip-retarding upper torso restraint harness to provide even greater slip-friction during crash impact.